Rotatable knob system configuration

ABSTRACT

A rotatable knob system includes: a panel comprising a plurality of sensor electrodes; and a rotatable knob interface comprising a rotary wheel and a fixed base, wherein the fixed base comprises knob sensing electrodes and a ground pad. The knob sensing electrodes of the fixed base are disposed over the knob sensing electrodes of the plurality of sensor electrodes of the panel, and the ground pad is disposed over reference electrodes of the panel. The panel comprises a plurality of traces which connect the knob sensing electrodes of the panel to a processing system, and the plurality of traces connecting the knob sensing electrodes of the panel to the processing system do not overlap with the reference electrodes of the panel.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims benefit to U.S. Provisional Patent ApplicationNo. 63/389,623, filed on Jul. 15, 2022, which is hereby incorporated byreference herein in its entirety.

BACKGROUND

Input devices including proximity sensor devices may be used in avariety of electronic systems. A proximity sensor device may include asensing region, demarked by a surface, in which the proximity sensordevice determines the presence, location, force and/or motion of one ormore input objects. Proximity sensor devices may be used to provideinterfaces for the electronic system. For example, proximity sensordevices may be used as input devices for larger computing systems, suchas touchpads integrated in, or peripheral to, notebook or desktopcomputers. Proximity sensor devices may also often be used in smallercomputing systems, such as touch screens integrated in cellular phones.

Additionally, proximity sensor devices may be implemented as part of amultimedia entertainment system of an automobile. In such cases, a knobmay be interfaced to a proximity sensor device.

SUMMARY

In an exemplary embodiment, the present disclosure provides a rotatableknob system. The rotatable knob system includes: a panel comprising aplurality of sensor electrodes; and a rotatable knob interfacecomprising a rotary wheel and a fixed base, wherein the fixed basecomprises knob sensing electrodes and a ground pad. The knob sensingelectrodes of the fixed base are disposed over the knob sensingelectrodes of the plurality of sensor electrodes of the panel, and theground pad is disposed over reference electrodes of the panel. The panelcomprises a plurality of traces which connect the knob sensingelectrodes of the panel to a processing system, and the plurality oftraces connecting the knob sensing electrodes of the panel to theprocessing system do not overlap with the reference electrodes of thepanel.

In a further exemplary embodiment, the panel is a touch-sensitivedisplay panel.

In a further exemplary embodiment, the panel comprises a plurality ofslices corresponding respectively to a plurality of analog front ends(AFEs), wherein the plurality of sensor electrodes of the panel includea first plurality of sensor electrodes corresponding to a first slice ofthe plurality of slices and a second plurality of sensor electrodescorresponding to a second slice of the plurality of slices.

In a further exemplary embodiment, the ground pad of the fixed base isdisposed over the first slice, and wherein the knob sensing electrodesof the fixed base are disposed over the second slice.

In a further exemplary embodiment, the ground pad of the fixed base andthe knob sensing electrodes of the fixed base are disposed in the sameslice.

In a further exemplary embodiment, the knob sensing electrodes of thefixed base are disposed over the second slice; the system furthercomprises the processing system; and the processing system is configuredto perform knob sensing via the knob sensing electrodes of the panel ina same time instance as performing touch sensing for the second slice.

In a further exemplary embodiment, the knob sensing electrodes of thefixed base are disposed over the second slice; the system furthercomprises the processing system; and the processing system is configuredto perform knob sensing via the knob sensing electrodes of the panel ina time instance during which touch sensing is not performed.

In another exemplary embodiment, the present disclosure provides arotatable knob system. The rotatable knob system includes: a panelcomprising a plurality of sensor electrodes; and a rotatable knobinterface comprising a rotary wheel and a fixed base, wherein the fixedbase comprises knob sensing electrodes and a ground pad. The knobsensing electrodes of the fixed base are disposed over the knob sensingelectrodes of the plurality of sensor electrodes of the panel, and theground pad is disposed over reference electrodes of the panel. The panelcomprises a first plurality of traces which connect the knob sensingelectrodes of the panel to a processing system and a second plurality oftraces which connect the reference electrodes of the panel to theprocessing system, wherein the second plurality of traces are separatefrom the first plurality of traces.

In a further exemplary embodiment, the panel is a touch-sensitivedisplay panel.

In a further exemplary embodiment, the panel comprises a plurality ofslices corresponding respectively to a plurality of analog front ends(AFEs), wherein the plurality of sensor electrodes of the panel includea first plurality of sensor electrodes corresponding to a first slice ofthe plurality of slices and a second plurality of sensor electrodescorresponding to a second slice of the plurality of slices.

In a further exemplary embodiment, the ground pad of the fixed base isdisposed over the first slice, and wherein the knob sensing electrodesof the fixed base are disposed over the second slice.

In a further exemplary embodiment, the ground pad of the fixed base andthe knob sensing electrodes of the fixed base are disposed in the sameslice.

In a further exemplary embodiment, the knob sensing electrodes of thefixed base are disposed over the second slice; the system furthercomprises the processing system; and the processing system is configuredto perform knob sensing via the knob sensing electrodes of the panel ina same time instance as performing touch sensing for the second slice.

In a further exemplary embodiment, the knob sensing electrodes of thefixed base are disposed over the second slice; the system furthercomprises the processing system; and the processing system is configuredto perform knob sensing via the knob sensing electrodes of the panel ina time instance during which touch sensing is not performed.

In yet another exemplary embodiment, the present disclosure provides amethod for knob sensing. The method includes: providing a rotatable knobinterface on a panel of an input device, the knob interface having afixed base and a rotary wheel, wherein the panel comprises a pluralityof sensor electrodes, wherein the fixed base comprises knob sensingelectrodes and a ground pad, wherein the knob sensing electrodes of thefixed base are disposed over the knob sensing electrodes of theplurality of sensor electrodes of the panel, and the ground pad isdisposed over reference electrodes of the panel, wherein the panelcomprises a plurality of traces which connect the knob sensingelectrodes of the panel to a processing system, and wherein theplurality of traces connecting the knob sensing electrodes of the panelto the processing system do not overlap with the reference electrodes ofthe panel; providing, by a processing system of the input device, areference signal to the reference electrodes of the panel and sensingsignals to the knob sensing electrodes of the panel; obtaining, by theprocessing system, resulting signals via the knob sensing electrodes ofthe panel; and determining a change in rotational position and adirection of rotation of the knob interface based, at least in part, onthe obtained resulting signals.

In a further exemplary embodiment, the panel comprises a plurality ofslices corresponding respectively to a plurality of analog front ends(AFEs), wherein the plurality of sensor electrodes of the panel includea first plurality of sensor electrodes corresponding to a first slice ofthe plurality of slices and a second plurality of sensor electrodescorresponding to a second slice of the plurality of slices.

In a further exemplary embodiment, the ground pad of the fixed base isdisposed over the first slice, and wherein the knob sensing electrodesof the fixed base are disposed over the second slice.

In a further exemplary embodiment, the ground pad of the fixed base andthe knob sensing electrodes of the fixed base are disposed in the sameslice.

In a further exemplary embodiment, the knob sensing electrodes of thefixed base are disposed over the second slice; and knob sensing isperformed via the knob sensing electrodes of the panel in a same timeinstance as performing touch sensing for the second slice.

In a further exemplary embodiment, the knob sensing electrodes of thefixed base are disposed over the second slice; and knob sensing isperformed via the knob sensing electrodes of the panel in a timeinstance during which touch sensing is not performed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 depicts an example input device with a rotatable knob interface.

FIG. 2 illustrates a cross-sectional side view of an example rotatableknob interface, according to one or more embodiments.

FIG. 3 illustrates an exploded view of the example rotatable knobinterface of FIG. 2 .

FIG. 4A illustrates an underside view of the fixed base of an examplerotatable knob interface as shown in FIG. 3 with a first set ofreference electrodes, and two sets of sensing electrodes according toone or more embodiments.

FIG. 4B illustrates an example portion of an input device with anelectrode grid, the grid configured into two sets of electrodes,according to one or more embodiments.

FIG. 4C illustrates the fixed base of an example rotatable knobinterface of FIG. 4A as positioned over the example sensor grid of FIG.4B, according to one or more embodiments.

FIG. 5 depicts a simplified illustration of a fixed base of a rotatableknob interface.

FIG. 6A depicts the fixed base of FIG. 5 overlaid on an exemplarydisplay panel having a plurality of sensing electrodes.

FIG. 6B depicts an illustrative example of capacitive loadings caused bygrounded reference electrodes and their corresponding vertical tracesbased on the location and orientation of the fixed base of a rotatableknob shown in FIG. 6A.

FIG. 7A depicts the fixed base of FIG. 5 overlaid on an exemplarydisplay panel having a plurality of sensing electrodes in accordancewith an exemplary embodiment of the present disclosure.

FIG. 7B depicts an illustrative example of capacitive loadings caused bygrounded reference electrodes and their corresponding vertical tracesbased on the location and orientation of the fixed base of a rotatableknob shown in FIG. 7A.

FIG. 8A depicts the fixed base of FIG. 5 overlaid on an exemplarydisplay panel having a plurality of sensing electrodes in accordancewith another exemplary embodiment of the present disclosure.

FIG. 8B depicts an illustrative example of capacitive loadings caused bygrounded reference electrodes and their corresponding vertical tracesbased on the location and orientation of the fixed base of a rotatableknob shown in FIG. 8A.

FIG. 9 is a process flowchart illustrating a method for implementing arotatable knob interface on an example electronic device, anddetermining a position and/or state of the rotatable knob interfaceaccording to one or more embodiments.

DETAILED DESCRIPTION

The following description may use perspective-based descriptions such astop/bottom, in/out, over/under, and the like. Such descriptions aremerely used to facilitate the discussion and are not intended torestrict the application of embodiments described herein to anyparticular orientation.

The following description may use the phrases “in one embodiment,” or“in one or more embodiments,” or “in some embodiments”, which may eachrefer to one or more of the same or different embodiments. Furthermore,the terms “comprising,” “including,” “having,” and the like, as usedwith respect to embodiments of the present disclosure, are synonymous.

The terms “coupled with,” along with its derivatives, and “connected to”along with its derivatives, may be used herein, including in the claims.“Coupled” or “connected” may mean one or more of the following.“Coupled” or “connected” may mean that two or more elements are indirect physical or electrical contact. However, “coupled” or “connected”may also mean that two or more elements indirectly contact each other,but yet still cooperate or interact with each other, and may mean thatone or more other elements are coupled or connected between the elementsthat are said to be coupled with or connected to each other. The term“directly coupled” or “directly connected” may mean that two or elementsare in direct contact.

As used herein, including in the claims, the term “circuitry” may referto, be part of, or include an Application Specific Integrated Circuit(ASIC), an electronic circuit, a processor (shared, dedicated, or group)and/or memory (shared, dedicated, or group) that execute one or moresoftware or firmware programs, a combinational logic circuit, and/orother suitable components that provide the described functionality.

FIG. 1 is a block diagram of an exemplary electronic device 100. Theelectronic device 100 may be configured to provide input to anelectronic system, and/or to update one or more devices. As used in thisdocument, the term “electronic system” (or “electronic device”) broadlyrefers to any system capable of electronically processing information.Some non-limiting examples of electronic systems include personalcomputers of all sizes and shapes, such as desktop computers, laptopcomputers, netbook computers, tablets, web browsers, e-book readers, andpersonal digital assistants (PDAs). Additional example electronicsystems include composite input devices, such as physical keyboards thatinclude the electronic device 100 and separate joysticks or keyswitches. Further example electronic systems include peripherals such asdata input devices (including remote controls and mice), and data outputdevices (including display screens and printers). Other examples includeremote terminals, kiosks, and video game machines (e.g., video gameconsoles, portable gaming devices, and the like). Other examples includecommunication devices (including cellular phones, such as smart phones),and media devices (including recorders, editors, and players such astelevisions, set-top boxes, music players, digital photo frames, anddigital cameras). Additionally, the electronic system could be a host ora slave to the input device. In other embodiments, the electronicssystem may be part of an automobile, and the electronic device 100represents one or more sensing devices of the automobile. In oneembodiment, an automobile may include multiple electronic devices 100,where each electronic device 100 may be configured differently than theother.

The electronic device 100 can be implemented as a physical part of theelectronic system, or can be physically separate from the electronicsystem. As appropriate, the electronic device 100 may communicate withparts of the electronic system using any one or more of the following:buses, networks, and other wired or wireless interconnections. Examplecommunication protocols include Inter-Integrated Circuit (I2C), SerialPeripheral Interface (SPI), Personal System/2 (PS/2), Universal SerialBus (USB), Bluetooth®, Radio Frequency (RF), and Infrared DataAssociation (IrDA) communication protocols.

In one or more embodiments, the electronic device 100 may utilize anycombination of sensor components and sensing technologies to detect userinput. For example, as illustrated in FIG. 1 , the electronic device 100comprises one or more electrodes 125 that may be driven to detectobjects or update one or more devices. In one embodiment, the electrodes125 are sensor electrodes of a capacitive sensing device. In suchembodiments, electrodes 125 include one or more common voltageelectrodes. In other embodiments, the electrodes 125 are electrodes ofan image sensing device, radar sensing device, and ultrasonic sensingdevice. Further yet, the electrodes 125 may be display electrodes of adisplay device. In some embodiments the electrodes 125 of the electronicdevice 100 are comprised of the common electrodes and have a commonshape. Some of the examples described herein include a matrix sensorinput device. As described in detail below, electronic device 100 may beprovided with a rotatable knob interface 150, which may interact withsome or all of electrodes 125.

The sensor electrodes 125 may have any shape, size and/or orientation.For example, the sensor electrodes 125 may be arranged in atwo-dimensional array as illustrated in FIG. 1 . Each of the sensorelectrodes 125 may be substantially rectangular in shape. In otherembodiments, the sensor electrodes 125 may have other shapes. Further,each of the sensor electrodes 125 may have the same shape and/or size.In other embodiments, at least one sensor electrode may have a differentshape and/or size than another sensor electrode. In various embodiments,the sensor electrodes 125 may be diamond shaped, have interdigitatedfingers to increase field coupling, and/or have floating cut-outs insideto reduce stray capacitance to nearby electrical conductors.

In one or more embodiments, some capacitive implementations utilize“self-capacitance” (or “absolute capacitance”) sensing methods based onchanges in the capacitive coupling between sensor electrodes and aninput object. In various embodiments, an input object near the sensorelectrodes, such as, for example, finger or stylus 145, alters theelectric field near the sensor electrodes 125, thus changing themeasured capacitive coupling. In one implementation, an absolutecapacitance sensing method operates by modulating sensor electrodes withrespect to a reference voltage (e.g., system ground), and by detectingthe capacitive coupling between the sensor electrodes and input objects.

Some capacitive implementations utilize “mutual capacitance” (or“transcapacitance”) sensing methods based on changes in the capacitivecoupling between sensor electrodes. In various embodiments, an inputobject near the sensor electrodes alters the electric field between thesensor electrodes, thus changing the measured capacitive coupling. Inone implementation, a transcapacitive sensing method operates bydetecting the capacitive coupling between one or more transmitter sensorelectrodes (also “transmitter electrodes” or “transmitters”) and one ormore receiver sensor electrodes (also “receiver electrodes” or“receivers”). Transmitter sensor electrodes may be modulated relative toa reference voltage (e.g., system ground) to transmit transmittersignals. Receiver sensor electrodes may be held substantially constantrelative to the reference voltage, or modulated with reference to thetransmitter sensor electrodes to facilitate receipt of resultingsignals. A resulting signal may comprise effect(s) corresponding to oneor more transmitter signals, and/or to one or more sources ofenvironmental interference (e.g., other electromagnetic signals). Sensorelectrodes may be dedicated transmitters or receivers, or may beconfigured to both transmit and receive.

Capacitive sensing devices may be used for detecting input objects inproximity to and/or touching input devices. Further, capacitive sensingdevices may be used to sense features of a fingerprint. Still further,as in the example of FIG. 1 , in one or more embodiments, capacitivesensing devices may be provided with a rotatable knob interface that iscoupled to the capacitive sensing device, and may be used to sense therotary position of the rotary knob. In some embodiments that include therotatable knob interface, the rotatable knob interface may have a homeposition and a compressed position, and the sensing device may also beused to determine when the rotatable knob is in the home position, andwhen it is in the compressed position, based on a change in capacitivecoupling of one or more of electrodes 125.

Continuing with reference to FIG. 1 , a processing system 110 is shownas part of the electronic device 100. The processing system 110 isconfigured to operate hardware of the electronic device 100. Asillustrated in FIG. 1 , processing system 110 comprises a driver module140, which may include a signal generator. In one or more embodiments,the driver module 140 generates sensing signals with which to driveelectrodes 125. In various embodiments, the processing system 110comprises parts of or all of one or more integrated circuits (ICs)and/or other circuitry components.

In some embodiments, the processing system 110 also compriseselectronically-readable instructions, such as firmware code, softwarecode, and/or the like. In some embodiments, components composing theprocessing system 110 are located together, such as, for example, nearsensing element(s) of the electronic device 100. In other embodiments,components of processing system 110 are physically separate with one ormore components in proximity to the sensing element(s) of electronicdevice 100, and one or more components elsewhere. For example, theelectronic device 100 may be a peripheral coupled to a desktop computer,and the processing system 110 may comprise software configured to run ona central processing unit (CPU) of the desktop computer and one or moreintegrated circuits (ICs) (perhaps with associated firmware) separatefrom the CPU. As another example, the electronic device 100 may bephysically integrated in a phone, and the processing system 110 maycomprise circuits and firmware that are part of a main processor of thephone. Further yet, the processing system 110 may be implemented withinan automobile, and the processing system 110 may comprise circuits andfirmware that are part of one or more of the electronic control units(ECUs) of the automobile. In some embodiments, the processing system 110is dedicated to implementing the electronic device 100. In otherembodiments, the processing system 110 also performs other functions,such as operating display screens, driving haptic actuators, etc.

The processing system 110 may be implemented as one or more modules thatoperate different functions of the processing system 110 (e.g., drivermodule 140, or determination module 141). Each module may comprisecircuitry that is a part of the processing system 110, firmware,software, or a combination thereof. In various embodiments, differentcombinations of modules may be used. Example modules include hardwareoperation modules for operating hardware such as sensor electrodes anddisplay screens, data processing modules for processing data such assensor signals and positional information, and reporting modules forreporting information. Further example modules include sensor operationmodules configured to operate sensing element(s) to detect input,identification modules configured to identify gestures such as modechanging gestures, and mode changing modules for changing operationmodes. In some embodiments, the electronic device 100 may be implementedas a chip, or as one or more chips. In some embodiments, the electronicdevice 100 may comprise a controller, or a portion of a controller, ofelectronic device 100.

In one or more embodiments, a display driver (e.g., driver module 140)may be configured for both display updating and input sensing, and may,for example, be referred to as including touch and display driverintegration (TDDI) technology. In such embodiments, driver module 140may be implemented as a TDDI chip, or a portion of a TDDI chip. In oneor more embodiments, the electronic device may include matrix sensor andmay also include TDDI technology.

In one or more embodiments, the processing system 110 further includesdetermination module 141. In one or more embodiments, the determinationmodule 141 may be configured to determine changes in a capacitivecoupling between each modulated sensor electrode and an input object,such as input objects 145, from the resulting signals. In oneembodiment, all of sensor electrodes 125 may be simultaneously operatedfor absolute capacitive sensing, such that a different resulting signalis simultaneously received from each of the sensor electrodes or acommon resulting signal from two or more sensor electrodes. In anotherembodiment, some of the sensor electrodes 125 may be operated forabsolute capacitive sensing during a first period and others of thesensor electrodes 125 may be operated for absolute capacitive sensingduring a second period that is non-overlapping with the first period.

In some embodiments, the processing system 110 responds to user input(or lack of user input) directly by causing one or more actions. Exampleactions include changing operation modes, as well as graphic userinterface (GUI) actions such as cursor movement, selection, menunavigation, and other functions. In some embodiments, the processingsystem 110 provides information about the input (or lack of input) tosome part of the electronic system (e.g., to a central processing systemof the electronic system that is separate from the processing system110, if such a separate central processing system exists). In someembodiments, some part of the electronic system processes informationreceived from the processing system 110 to act on user input, such as tofacilitate a full range of actions, including mode changing actions andGUI actions. Further, in some embodiments, the processing system 110 isconfigured to identify one or more objects, and the distance to theseobjects. In some embodiments the processing system 110 is configured toidentify one or more rotational changes of knob interface 150, or one ormore changes of state of knob interface 150, or both, and map thosechanges to desired actions.

For example, in some embodiments, the processing system 110 operateselectrodes 125 to produce electrical signals (resulting signals)indicative of input (or lack of input) in a sensing region. Theprocessing system 110 may perform any appropriate amount of processingon the electrical signals in producing the information provided to theelectronic system. For example, the processing system 110 may digitizeanalog electrical signals obtained from the electrodes 125. As anotherexample, the processing system 110 may perform filtering or other signalconditioning, or, as yet another example, the processing system 110 maysubtract or otherwise account for a baseline, such that the informationreflects a difference between the electrical signals and the baseline.As yet further examples, the processing system 110 may determinepositional information, recognize inputs as commands, recognizehandwriting, recognize fingerprint information, distance to a targetobject, and the like.

“Positional information” as used herein broadly encompasses absoluteposition, relative position, velocity, acceleration, and other types ofspatial information. Exemplary “zero-dimensional” positional informationincludes near/far or contact/no contact information. Exemplary“one-dimensional” positional information includes positions along anaxis. Exemplary “two-dimensional” positional information includesmotions in a plane. Exemplary “three-dimensional” positional informationincludes instantaneous or average velocities in space. Further examplesinclude other representations of spatial information. Historical dataregarding one or more types of positional information may also bedetermined and/or stored, including, for example, historical data thattracks position, motion, or instantaneous velocity over time.

It should be understood that while many embodiments of the disclosureare described in the context of a fully functioning apparatus, themechanisms of the present disclosure are capable of being distributed asa program product (e.g., software) in a variety of forms. For example,the mechanisms of the present disclosure may be implemented anddistributed as a software program on information bearing media that arereadable by electronic processors (e.g., non-transitorycomputer-readable and/or recordable/writable information bearing mediareadable by the processing system 110). Additionally, the embodiments ofthe present disclosure apply equally regardless of the particular typeof medium used to carry out the distribution. Examples ofnon-transitory, electronically readable media include various discs,memory sticks, memory cards, memory modules, and the like.Electronically readable media may be based on flash, optical, magnetic,holographic, or any other storage technology.

In one or more embodiments, the processing system 110 is configured togenerate a voltage signal to drive the electrodes 125 during a displayupdate interval and an input sensing interval, respectively. In suchembodiments, the voltage signal generated to drive the electrodes 125during a display update interval is a substantially constant, or fixedvoltage, and the voltage signal generated to drive the electrodes 125during an input sensing interval may be referred to as a sensing signal,having a waveform with a periodically variable voltage. In one or moreembodiments, the value of a voltage signal to drive the electrodes 125during a display update interval may be predetermined. For example, thevoltage value may be provided by a manufacturer of electronic device 100and/or the electrodes 125, and may be device-specific to electronicdevice 100.

In one embodiment, the driver module 140 comprises circuitry configuredto provide the sensing signal. For example, the driver module circuitrymay include an oscillator, one or more current conveyers and/or adigital signal generator circuit. In one embodiment, the driver modulecircuitry generates the voltage signal based on a clock signal, theoutput of the oscillator and the parameters discussed above.

As noted above, in one or more embodiments, the driver module 140generates a signal to drive the electrodes 125 during each of thedisplay update periods and input sensing update periods. In suchembodiments, an input sensing update period is provided in between twodisplay update periods. In some implementations, the input sensingupdate period may be of a shorter duration than a display update period.In such embodiments, there are several display update periods and inputsensing update periods per display frame. In one or more embodiments, byacquiring the resulting signals over successive input sensing periodsthe rotation of the rotatable knob interface 150, as well as whether itis in its home state or compressed state, may be tracked.

As noted above, in one or more embodiments, an additional inputapparatus may be provided on top of the display panel 120 of theelectronic device 100, such as, for example, the rotatable knobinterface 150, and may be coupled to some or all of electrodes 125 thatare positioned near or below it. In one or more embodiments, theadditional apparatus may provide alternate ways for a user to provideinput to electronic device 100 other than touching, or hovering near, adisplay screen with a finger or stylus 145. In the depicted example ofFIG. 1 , the rotatable knob interface 150 is mounted onto the displaypanel 120, and may have a full (as shown in FIG. 1 ) or partial overlapwith the display panel 120. As noted, in one or more embodiments therotatable knob interface 150 may have a stationary base (not visible inthe top view of FIG. 1 ) that is provided with various sets of couplingelectrodes configured to couple with respective sets of electrodes ofthe display panel 120, such as one or more sets of electrodes that areprovided with sensing signals and one or more sets of electrodes thatare provided with reference signals. In one or more embodiments, thestationary base may include different conductive regions respectivelyconnected to corresponding sets of coupling electrodes.

In one or more embodiments, the rotatable knob interface 150 alsoincludes a rotary wheel that sits above, and rotates relative to, thestationary base. In such embodiments, an underside of the rotary wheelis patterned with various conductive and non-conductive regions in aperipheral region 152, configured to align with the conductive regionsof the stationary base so that there are various electrical couplingsbetween the conductive regions of the stationary base and the variousconductive and non-conductive regions in the peripheral region 152 ofthe rotary wheel. These components are further configured such thatthese electrical couplings change as the rotary wheel is rotated, insuch manner that by detecting the effects of the changes in theelectrical couplings on resulting signals received on the display panel,the input device can determine a rotation, or a change in rotation, ofthe knob interface. In one or more embodiments, patterned region 152 mayhave numerous possible example arrangements of the conductive andnon-conductive regions, and there may be various ways of having therotary wheel and the stationary base electrically interact as the rotarywheel is rotated. Thus, alternate configurations and relativearrangements of both the conductive regions of the stationary base, andthe placement of the conductive and non-conductive regions of the rotarywheel are possible, all being within the scope of this disclosure.

In one or more embodiments, the rotation imparted to the rotatable knobinterface by a user, in either relative or absolute terms, may bedetected by the electronic device 100. In one or more embodiments, therotatable knob interface 150 may also be pressed downwards by a user,and may thus have two positions, a home, or “uncompressed” position, anda “compressed” position, which a user maintains by, for example, pushingdown on the knob interface 150 against one or more biasing springs. Inone or more embodiments, the rotatable knob interface 150 has a cover.In alternate embodiments, the rotatable knob interface may be presseddownwards so as to rest at multiple positions, and thus may havemultiple states between an “uncompressed” and a “fully compressed”position. In the home position the cover is at a greater distance abovethe rotary wheel than in the compressed position. In one or moreembodiments, the rotary wheel may have several switches provided betweenit and the cover, these switches may include the biasing springs. Insuch embodiments, the rotatable knob interface 150 may be provided witha fourth set of coupling electrodes, which couple to electrodes of theinput device that are also driven with sensing signals. In the exampleof FIG. 1 , the fourth set of coupling electrodes is connected to aninner ring provided in the stationary base, which aligns with asimilarly shaped inner ring 153 that is provided in the rotary wheel. Insuch embodiments, when a user presses down on the cover of the rotatableknob interface, so that the rotatable knob interface 150 is then in the“compressed” position, the switches close so as to connect the innerring 153 of the rotary wheel with all of the conductive regions providedin patterned region 152. This serves to electrically couple the fourthset of coupling electrodes of the stationary base to the first set ofcoupling electrodes of the stationary base, thereby coupling acorresponding fourth set of electrodes of the display panel to areference signal. However, when the user ceases to press down on thecover, the fourth set of coupling electrodes of the knob interfacesimply floats. In one or more embodiments, direction and degree ofrotation, as well as a user pressing down on, or ceasing to press downupon, the rotatable knob interface 150, may be interpreted by processingsystem 110, such as, for example, by determination module 141, and maybe mapped to various user input actions, signals, or directives.

It is noted that in one or more embodiments a user may rotate therotatable knob interface 150 in various ways, for example, grabbing anouter housing of the rotatable knob interface and turning it, grabbing atop of the rotatable knob interface, or a flange protruding from theside of the rotatable knob interface and turning it, or placing one ormore fingertips in or on a recessed channel on an upper surface of therotatable knob interface.

In one or more embodiments, the electronic device 100 of FIG. 1 may beprovided in an automobile. For example, it may be affixed to asubstantially vertical display screen provided in a central part of adashboard. In one or more embodiments, all the electrodes not physicallyblocked by the rotatable knob interface 150, whether the electrodes 125are inside or are outside of region 155 (described below), remainactive. Thus, in such embodiments, both touches away from the knob, androtations of the knob, are detected and reported by the electrodes 125at the same time.

In alternate embodiments, all other forms of user input besides thosereceived via the rotatable knob interface 150 may be disabled on theelectronic device. Thus, in such embodiments, the electrodes 125 are notdriven during the sensing interval to perform their standard sensingfunctionality. As a result, if a finger or other object 145 is movedinto, or away from, its vicinity, no resulting signal is obtained, or ifobtained, it is not processed. In such alternate embodiments, this maybe done to prevent a driver of the automobile from attempting to touchthe display 120 while driving, as a safety measure, and thus to onlyinteract with the electronic device 100 via the rotatable knob interface150. In such alternate embodiments, the disabling of standard sensingfunctionality of the electrodes 125 may be implemented during specifiedactivities of the automobile, but not during others. For example, thedisabling of standard sensing functionality of the electrodes 125 may beimplemented while the automobile is in actual motion, but at all othertimes some of the electrodes 125, for example, those not near enough tothe rotatable knob interface to interfere with signals acquired from it,may be operated to perform standard sensing, as described above.

Thus, in some alternate embodiments, when all of the electrodes 125 aredisabled from standard sensing, whether during actual driving of theautomobile, or whether at all times, as the case may be, the only waythat a driver of the automobile can provide input to the electronicdevice 100 is via the rotatable knob interface 150, using a pre-definedset of rotations and/or pressings of the rotatable knob interface 150.These motions modify a resulting signal which is received by theelectronic device 100 during a sensing period, which then interpretsthem, for example, using determination module 141. The resulting signalmay be the same signal as the sensing signal that driver module 140drives an electrode 125 with, after being modified by the capacitivecoupling of the rotary knob interface 150.

In other alternate embodiments, for example, only some of the electrodes125, in particular those that are near or beneath the rotary knobinterface 150, are disabled from standard capacitive sensing, and theremainder of the electrodes 125 on the electronic device 100 may stillbe operative for standard capacitive sensing. In such alternateembodiments, the electrodes that are disabled for standard capacitivesensing are those that are close enough to the rotatable knob interface150 such that driving them with standard sensing signals may interferewith the resulting signals obtained from various sets of the electrodes125 that are respectively coupled to the coupling electrodes of therotatable knob interface 150. To illustrate this feature, in FIG. 1there is shown a dashed line boundary 155. Electrodes 125 within theboundary 155 are in a “blackout zone” and not driven with a standardsensing signal. Rather, as described in detail below, any of theelectrodes within the blackout zone that are coupled to the rotatableknob interface are driven so as to capture rotations and compressions ofthe rotatable knob interface, as described below.

In general, within the blackout zone, a first, second and third set ofthe electrodes 125 are coupled to corresponding first, second and thirdsets of the coupling electrodes of the stationary base of the rotatableknob interface 150. In embodiments, the first set are driven with areference signal, and the second and third sets are driven with asensing signal to obtain a resulting signal modified by the then extantrelative rotational relationship of the stationary base and the rotarywheel of the rotatable knob interface 150. Thus, in each of thesealternate embodiments, all of the electrodes within the blackout zoneboundary 155 may be disabled from standard capacitive sensing at alltimes.

As used herein, the term “disabled electrode” may refer to an electrodethat is not driven at all, an electrode that is driven with a guardsignal, or one that is driven with a constant signal.

Continuing with reference to FIG. 1 , as noted above, sets of electrodesof the electronic device 100 are coupled to corresponding sets ofcoupling electrodes of the rotatable knob interface 150. Thus, during aninput sensing period a reference signal is supplied by the driver module140 to a first set of the electrodes 125, and a sensing signal issupplied to second and third sets of the electrodes 125. In one or moreembodiments, the reference signal may be a configurable direct current(DC) output provided by the processing system 110. In some embodiments,the DC signal may be a ground signal of the electronic device 100. Insome embodiments, a resulting signal is obtained from each of the secondand third sets of the electrodes 125, where the resulting signals is thesensing signal as modified by the rotational state of the rotatable knobinterface 150. The resulting signals are interpreted by thedetermination module 141 to determine a rotation of the rotatable knobinterface 150. In one or more embodiments, the rotation may bedetermined in relative terms, such as, for example, a differentialangular change from a prior position, or, for example, in absoluteterms, such as, for example, a positive or negative angular change froma home position. In some embodiments, if the rotatable knob is turnedmore than a full 360 degree turn, the overall rotational distance thatit has covered may also be measured. In such embodiments, one or moreuser commands may be mapped to absolute rotational distance. Inalternate embodiments, only the one or both of overall angular changebetween starting position and ending position, or final absolute angularposition, is measured.

FIG. 2 illustrates six main components of an example rotatable knobinterface, according to one or more embodiments. With reference thereto,starting at the bottom of the example device, there is shown a fixedbase 231. In some embodiments, the fixed base 231 does not move as auser rotates the example knob interface. Thus, in some embodiments, itis affixed to the surface of an example input device, such as, forexample, by an adhesive. In some embodiments, the fixed base 231 isaffixed to the input device in a semi-permanent or permanent manner, andis placed thereon so as to align with a grid of electrodes provided inthe input device. Provided above the fixed base 231 is a rotary wheel230. The rotary wheel 230 turns as a user rotates the knob interface,such as, for example, by grasping and turning cover cap 215, asdescribed below. At an inner side of the rotary wheel 230 is provided avertical ring bearing 225. The vertical ring bearing 225 isnon-conductive, and may be made of plastic, for example, and may havethe shape of a ring. Vertical ring bearing 225 may have a substantiallytubular shape. As described below with reference to FIG. 3 , there is anadditional substantially horizontal ring-shaped bearing upon which therotary wheel 230 sits, according to one or more embodiments. By usingboth of the bearings, frictional forces between the fixed base 231, andthe rotary wheel 230 may be reduced.

Continuing with reference to FIG. 2 , provided on top of rotary wheel230 are one or more switches 220. For example, switches 220 may be domeswitches. There may be three switches 220, and the switches may beequidistantly placed on an upper surface of rotary wheel 230. Asdescribed more fully below, in one or more embodiments, the switches areused to distinguish between two states of the knob interface, namely acompressed state, in which the switches are closed, and an uncompressedstate in which the switches remain open. The compression state of theknob interface is orthogonal to its internal rotational position. Thus,the knob interface may be rotated while in either a compressed or anuncompressed state (and in any position in between the two states), andthat rotation may be sensed and measured. Similarly, the state of theswitches as being open or closed, corresponding respectively to the knobinterface being in the “home” or uncompressed state, or in thecompressed state, may be detected whether or not the rotatable knobinterface is rotationally stationary or being rotated.

Finally, continuing still with reference to FIG. 2 , the knob interfacehas an inner cap 210, and a cover cap 215, as shown. In operation, auser physically interacts with cover cap 215, for example, by graspingcover cap 215 and rotating the rotary wheel 230 relative to the fixedbase 231, or by pushing down on cover cap 215 to compress the knobinterface and close the switches 220. As shown, the inner cap 210 isattached, by prongs 211, to a lip provided on the inner surface ofvertical ring bearing 225. The cover cap 215 is attached to the innercap 210, such that turning the outer cap 215 rotates the rotary wheel230.

FIG. 3 illustrates an exploded view of the example rotatable knobinterface of FIG. 2 , illustrating the upper side of various components.With reference to FIG. 3 , beginning at the bottom of the figure, thereis shown the upper surface of fixed base 231. The upper surface isprovided with a conductive peripheral ring 235, to be coupled to areference signal of an input device to which the rotary knob is to beattached. As shown, the upper surface also shows an inner conductingring 232 as well as two conductive pads 237 and 238. In one or moreembodiments, these three conductive regions are configured to be coupledto a sensing signal of the input device.

Continuing with reference to FIG. 3 , there are also shown the verticalring bearing 225 and a horizontal ring-shaped bearing 226 configured toslide over it. In one or more embodiments, because the fixed base 231has a smaller inner diameter than the rotary wheel 230, there is a ledgeat the inner periphery of the fixed base 231 upon which the verticalring bearing 225 may sit. The vertical ring bearing 225 is thusconfigured to fit inside the inner diameter of the horizontal ringbearing 226, and rest upon the inner periphery of the fixed base 231.The two bearings thus provide a physical interface between the fixedbase 231 and the rotary wheel 230, as noted above, which reducesfriction between them as the rotary wheel 230 is moved.

Continuing further with reference to FIG. 3 , there are also shown threeswitches 220 provided around the upper surface of rotary wheel 230. Asnoted, these switches may be dome switches, for example. Above theswitches 220 is shown the inner cap 210, which is configured to fitinside the vertical ring bearing 225, and be secured to the verticalring bearing 225 via three prongs 211, which, in one or more embodimentsare also placed equidistantly around the inner vertical surface of thevertical ring bearing 225. As shown, the inner cap 210 has asubstantially horizontal upper ring, and a lower hollow cylindricalshaped portion. Thus, in one or more embodiments, the outer diameter ofthe lower cylindrical shaped portion of the inner cap 210, is designedto fit within an inner diameter of the vertical ring bearing 225, andthen clamp to the bottom surface of the vertical ring bearing 225 by theprongs 211, which slightly protrude under such bottom surface when theinner cap 210 is in the home or uncompressed position. Finally, withreference to FIG. 3 , the cover cap 215 is attached to the upper ringportion of the inner cap 210, as shown.

FIGS. 4A through 4C, next described, illustrate the spatialrelationships between coupling electrodes provided on the bottom surfaceof the fixed base 231, respectively connected to correspondingconducting regions on the top surface of the fixed base 231, andelectrodes in a grid provided in an example input device.

FIG. 4A illustrates a view of the underside of the fixed base 231 of anexample rotatable knob interface shown in FIG. 3 , superimposed over agrid of electrodes 401 of an example input device, according to one ormore embodiments. With reference thereto, the bottom, or underside, offixed base 231 has three sets of electrodes. A first set 430, shown asshaded, is a connected set of electrodes configured to receive areference signal from the input device. Three electrodes 410, 420, 411,grouped into the remaining two sets, are configured to receive sensingwaveforms of the input device. The second set, including electrodes 410and 411, is configured to sense rotation of the knob interface. Thethird set, including electrode 420, is configured to sense a “click” orthe closing of the switches 220, for example, when a user pushes theknob interface into its compressed state. As shown, the sensingelectrodes 410, 411 and 420 are designed to each overlap with, to theextent possible, a full input device electrode (e.g., a square) of grid401. On the other hand, the set of electrodes 430 may be designed toeach overlap portions of multiple electrodes of grid 401, but not fullelectrodes, such that the set of electrodes 430 only pick up signal fromthe corresponding reference electrodes 403 (see FIG. 4B) on the grid 401on the upper surface of the example input device, and do not pick up anyparasitic capacitance from neighboring sensing electrodes. Thisisolation is illustrated in FIG. 4A by two features. First, there is anempty column 412 of sensing pixels to the right of sensing electrodes410, 411 and 420 that provides a gap between the sensing electrodes 410,411 and 420, and the set of electrodes 430. Second, the set ofelectrodes 430 (full line shading) are each recessed inwardly relativeto the reference electrodes 403 (shaded with dotted lines) by, forexample, 1.5-2 mm. This recessing helps the set of electrodes 430 toonly pick up the reference electrode signal and much less so of theparasitic coupling of nearby sensing signals on sensing electrodes 402.Further, this feature also helps with tolerance alignment of the examplerotatable knob interface to the input device.

FIG. 4B illustrates the example grid 401 of FIG. 4A divided into twotypes of electrodes, according to one or more embodiments. In general,each electrode of an input device's grid may be selectively chosen to bedriven with a sensing waveform or a reference signal, such as, forexample, ground, or other reference signal. In one or more embodiments,to coordinate its grid with the electrodes of the underside of a fixedbase, as shown in FIG. 4A, the input device's grid may be arranged asshown in FIG. 4B. Thus, grid electrodes 403, shaded in FIG. 4B, may bedriven by the input device with a reference signal, and grid electrodes402 may be driven by the input device with a sensing signal. In one ormore embodiments, when this scheme is implemented, there is a pairingbetween the underside of the fixed base 231, and the electrodes of grid401 of an input device. This is illustrated in the superimposed view ofFIG. 4C.

FIG. 4C thus illustrates the underside of fixed base 231 of FIG. 4A aspositioned over the example input device electrode grid 401 of FIG. 4B,according to one or more embodiments. As shown, the sensing electrodes410, 411 and 420, configured for sensing on the knob interface, are eachsubstantially fully aligned with grid electrodes 402, to be driven withsensing waveforms. In one embodiment, they are driven with the samesensing waveforms. Similarly, the set of electrodes 430, configured forcoupling to a reference signal of the input device, are each providedabove multiple grid electrodes 403, to be driven with a reference signalby the input device. In one or more embodiments, because the fixed base231 is stationary, and fixed in position relative to the input device,it is first aligned to the electrodes of the input device, as shown, andthen, in one or more embodiments, permanently attached to a glasssurface of the input device.

Thus, as shown, for example, in FIGS. 4A-4C, an exemplary rotatable knobmay include a fixed base 231, which may be disposed over an array ofelectrodes of an input device (such as the sensing electrodes of atouchscreen display panel). Fixed base 231 may include two sensingelectrodes 410, 411 on the fixed base 231 for sensing rotation of theknob interface, and the fixed base 231 may further include a ground pad430, which may correspond to a set of grounded electrodes on the fixedbase 231 which are configured to couple to corresponding groundedelectrodes 403 of the input device driven with a reference signal andthereby provide capacitive loading for knob sensing through the sensingelectrodes of the fixed base.

FIG. 5 depicts a simplified illustration of a fixed base 231 of arotatable knob interface. Fixed base 231 includes knob sensingelectrodes 410 and 411 corresponding respectively to sensing channels“A” and “C”. The fixed base 231 also includes a ground pad 430corresponding to a ground channel “GND”.

FIG. 6A depicts the fixed base 231 of FIG. 5 overlaid on an exemplarydisplay panel having a plurality of sensing electrodes. The plurality ofsensing electrodes may be sensor pads for absolute capacitance sensingarranged in a sensor grid 401 (wherein each square corresponds to arespective sensing electrode formed as a sensor pad). The sensor grid401 may include several “slices” corresponding to respective “muxes.” InFIG. 6A, six slices are depicted (corresponding to the regions labeled“AFE_MUX1” through “AFE_MUX6”), wherein each respective slice includes 6columns of 20 sensing electrodes, and the sensing electrodes in eachrespective slice are coupled to a respective analog front end (AFE)portion of a processing system. It will be appreciated that displaypanels may have different numbers of slices in differentimplementations, and that respective slices may include differentnumbers of sensing electrodes in different implementations. It willfurther be appreciated that a processing system may operate the sensorgrid 401 in a time-division-multiplexed manner, with sensing for eachrespective slice being performed in a respective time instance for thatslice (in one respective time instance corresponding to a respectiveslice, one measurement is obtained via each sensing electrode undermeasurement within the slice, such that respective measurements areobtained for all respective sensing electrodes under measurement withinthe slice during the one time instance).

In the configuration shown in FIG. 6A, knob sensing electrodes 410 and411 of fixed base 231 respectively overlap knob sensing electrodes 402 aand 402 c of sensor grid 401, and ground pad 430 of fixed base 231overlaps reference electrodes 403 of sensor grid 401. Thus, thereference electrodes 403 are configured to provide a reference groundsignal to ground pad 430 of fixed base 231, and knob sensing electrodes402 a and 402 c are configured to obtain knob rotation sensing signalsfrom knob sensing electrodes 410 and 411 of fixed base 231.

For column-shaped slices (such as AFE_MUX1 through AFE_MUX6 of FIG. 6A),a plurality of vertical traces (which may be M3 wires) are disposed overeach respective column of sensing electrodes to carry signals fromrespective sensing electrodes to a respective analog front end (AFE)corresponding to the respective slice that contains the respectivecolumn of sensing electrodes. Thus, for example, in the second columnwithin AFE_MUX2, the vertical traces for that column overlap both theknob sensing electrodes 402 a and a subset of electrodes out of thereference electrodes 403 such that vertical traces which carry areference ground signal for ground pad 430 pass over knob sensingelectrodes 402 a. This results in extra loading on knob sensingelectrodes 402 a, and thereby causes a slower settling time of the knobsensing waveform corresponding to knob sensing electrodes 402 a andresults in worse sensing performance (e.g., with respect to sensingspeed and signal-to-noise ratio (SNR)). Similarly, for example, in thefourth column within AFE_MUX2, the vertical traces for that columnoverlap both the knob sensing electrodes 402 c and a subset ofelectrodes out of the reference electrodes 403 such that vertical traceswhich carry a reference ground signal for ground pad 430 pass over knobsensing electrodes 402 c. This results in extra loading on knob sensingelectrodes 402 c, and thereby causes worse sensing performance withrespect to those knob sensing electrodes as well. Further, the verticaltraces which carry a reference ground signal for ground pad 430 may beproximate to a nearby display source line (which may also be verticallydisposed in the same column), thereby loading the display line andcausing interference associated with the display.

It will be appreciated that the vertical traces of each respectiveAFE_MUX connect sensor electrodes of the respective AFE_MUX to acorresponding respective AFE of the processing system (e.g., processingsystem 110 of FIG. 1 ). To perform knob sensing, the processing systemmay, for example, provide a reference signal to the reference electrodes403 and sensing signals to knob sensing electrodes 402 a, 402 c, as wellas obtain resulting signals from knob sensing electrodes 402 a, 402 c.

FIG. 6B depicts an illustrative example of how grounded referenceelectrodes and their corresponding vertical traces cause capacitiveloading on a nearby knob sensing pad and a nearby display source linebased on the location and orientation of the fixed base of a rotatableknob shown in FIG. 6A. In particular, as can be seen in FIG. 6B, thevertical trace 610 connected to a reference GND electrode 611 in thesecond column of AFE_MUX2 also overlaps the knob sensing pad in thesecond column of AFE_MUX2, thereby causing undesirable capacitiveloading 613 from the vertical trace 610 onto the knob sensing pad. Thus,in addition to the desired coupling 612 between the reference GNDelectrode and the knob sensing pad which provides knob loading for theknob sensing operation, there is also undesirable coupling 613 between agrounded vertical trace 610 and the knob sensing pad. Additionally, thereference GND electrode 611 itself is proximate to a display source line615 connected to a plurality of pixels of the display panel and causesundesirable capacitive loading 614 from the reference GND electrode ontothe display source line 615.

It will be appreciated that FIG. 6B is illustrative in the sense thatthe electrodes of the sensor grid depicted in FIG. 6B are not in a 1:1relationship relative to the electrodes of the sensor grid depicted inFIG. 6A, and that FIG. 6B is merely intended to conceptually illustratecertain capacitive loadings that exist during operation due to theconfiguration of the rotatable knob system depicted in FIG. 6A.

FIG. 7A depicts the fixed base 231 of FIG. 5 overlaid on an exemplarydisplay panel having a plurality of sensing electrodes in accordancewith an exemplary embodiment of the present disclosure. Relative to theconfiguration shown in FIG. 6A, the fixed base 231 in FIG. 7A has beenrotated 90°, and the fixed base 231 is disposed over both the AFE_MUX1and AFE_MUX2 regions such that the ground pad 430 of the fixed base 231is disposed entirely within the AFE_MUX1 region and the knob sensingelectrodes 410 and 411 of the fixed base 231 are disposed entirelywithin the AFE_MUX2 region. In this example, all electrodes of AFE_MUX1are grounded (such that the entirety of the AFE_MUX1 region can beconsidered as being the reference electrodes 403) while knob sensing isperformed within the AFE_MUX2 region through knob sensing electrodes 402a and 402 c. It will be appreciated that, in the example depicted inFIG. 7A, to perform touch sensing and knob sensing for the displaypanel, there may be seven distinct time instances for a full scan of thetouchscreen display panel, including six time instances for performingtouch sensing in the six AFE_MUX regions, as well as an additional timeinstance for performing knob sensing in the AFE_MUX2 region where theknob sensing electrodes for knob sensing are located.

FIG. 7B depicts an illustrative example of capacitive loadings caused bygrounded reference electrodes and their corresponding vertical tracesbased on the location and orientation of the fixed base of a rotatableknob shown in FIG. 7A. As shown in FIG. 7B, the reference electrodes ofAFE_MUX1 and their corresponding vertical traces, which are disposed inthe AFE_MUX1 region, do not result in capacitive loading being imposedon the knob sensing pad and the source display line 315 in the AFE_MUX2region, other than the desired coupling 612 between the reference GNDelectrode and the knob sensing pad which provides knob loading for theknob sensing operation. Thus, relative to the configuration shown inFIG. 6A, the configuration shown in FIG. 7A provides for faster settlingtime of the knob sensing channels, less interference with the displaysignal, and higher SNR.

FIG. 8A depicts the fixed base 231 of FIG. 5 overlaid on an exemplarydisplay panel having a plurality of sensing electrodes in accordancewith another exemplary embodiment of the present disclosure. Relative tothe configuration shown in FIG. 6A, the fixed base 231 in FIG. 8A hasbeen rotated 90°, and the fixed base 231 is disposed entirely within theAFE_MUX2 region in a manner such that vertical traces for the referenceelectrodes 403 do not overlap with the knob sensing electrodes 402 a and402 c. In this example, both touch sensing and knob sensing for theAFE_MUX2 region may be performed together in a single time instance forthe AFE_MUX2 region. It will thus be appreciated that, in the exampledepicted in FIG. 8A, to perform touch sensing and knob sensing for thedisplay panel, there may be six distinct time instances for a full scanof the touch screen display panel, including a first time instance forperforming touch sensing in the AFE_MUX1 region, a second time instancefor performing both touch and knob sensing in the AFE_MUX2 region, andthird, fourth, fifth and sixth time instances for performing touchsensing in the AFE_MUX3, AFE_MUX4, AFE_MUX5 and AFE_MUX6 regions,respectively.

FIG. 8B depicts an illustrative example of capacitive loadings caused bygrounded reference electrodes and their corresponding vertical tracesbased on the location and orientation of the fixed base of a rotatableknob shown in FIG. 8A. As shown in FIG. 8B, the reference GND electrodesof AFE_MUX2 and their corresponding vertical traces do not result incapacitive loading being imposed on the knob sensing pad and the sourcedisplay line 615, other than the desired coupling 612 between thereference GND electrode and the knob sensing pad which provides knobloading for the knob sensing operation. Thus, relative to theconfiguration shown in FIG. 6A, the configuration shown in FIG. 8Bprovides for faster settling time of the knob sensing channels, lessinterference with the display signal, and higher SNR.

Exemplary embodiments of the present disclosure provide for improvingthe performance of knob sensing systems wherein a rotatable knob isdisposed over a sensing array by avoiding undesirable capacitivecouplings between grounded traces of the sensing array and otherelements (including knob sensing electrodes and display source lines).Unlike conventional knob sensing systems in which grounded traces of thesensing array overlap with knob sensing electrodes, the fixed base of arotatable knob in accordance with exemplary embodiments of the presentdisclosure is oriented and located relative to a sensing array so as toavoid such overlap (and may further be oriented and located to avoid orminimize capacitive coupling from grounded traces of the sensing arrayto display source lines).

To test the efficacy of exemplary embodiments of the present disclosure,SNR measurements were conducted in connection with an exemplaryimplementation of a rotatable knob system according to the presentdisclosure and a conventional rotatable knob system. Through thesetests, the rotatable knob system according to the present disclosure wasshown to have improved SNR relative to a conventional rotatable knobsystem (for the systems tested, the improvement was about 7-8 dB onaverage, corresponding to an SNR improvement of about 100-150%).Additionally, the two systems were also tested under different knobstatuses (OFF/OFF and ON/ON) and under different image conditions (blackimage and white image), and it was demonstrated that, relative to aconventional rotatable knob system, the rotatable knob system accordingto the present disclosure avoided significant ADC shift corresponding todisplay image switching due to there being less loading on displaysource lines (ADC shift in this context refers to a shift in the valuesoutput by an analog-to-digital converter (ADC) of an AFE caused bycapacitive loading on display source lines relative to baselinereference ADC values).

FIG. 9 is a process flowchart illustrating a method 900 for implementinga rotatable knob interface on an example electronic device, anddetermining a position and/or state of the rotatable knob interfaceaccording to one or more embodiments. For example, the electronic devicemay be a combined display and sensing device, such as one that, forexample, includes TDDI technology, as described above.

Method 900 includes blocks 910 through 950. In alternate embodiments,method 900 may have more, or fewer, blocks. Method 900 begins at block910, where a rotatable knob interface is provided on an input device,the rotatable knob interface having a fixed base and a rotary wheel. Thepanel comprises a plurality of sensor electrodes, the fixed basecomprises knob sensing electrodes and a ground pad, the knob sensingelectrodes of the fixed base are disposed over the knob sensingelectrodes of the plurality of sensor electrodes of the panel, and theground pad is disposed over reference electrodes of the panel. The panelfurther comprises a plurality of traces which connect the knob sensingelectrodes of the panel to a processing system, and the plurality oftraces connecting the knob sensing electrodes of the panel to theprocessing system do not overlap with the reference electrodes of thepanel. Further, the fixed base has first, second and third sets ofcoupling electrodes on a bottom surface, and a top surface with aperipheral portion including first second and third regions electricallyconnected to each of the first, second and third sets of couplingelectrodes. The rotary wheel has a bottom surface provided withalternating conductive and non-conductive regions.

From block 910, method 900 proceeds to block 920, where the first set ofcoupling electrodes of the knob interface is capacitively coupled to afirst set of electrodes of the input device configured to provide areference signal. For example, the first set of electrodes may beelectrodes 430 of FIG. 4A. Or, for example, the set of first electrodesmay include a single electrode. As regards the reference signal, forexample, it may be a ground signal generated by processing circuitry ofthe electronic device, such as, for example, the processing circuitry110 of the electronic device 100 of FIG. 1 . As another example, thereference signal may be a ground signal output by a TDDI device from anarbitrarily chosen analog front end.

From block 920, method 900 proceeds to block 930, where the second andthird sets of coupling electrodes of the knob interface are capacitivelycoupled to second and third sets of electrodes of the input device, thesecond and third sets of electrodes configured to receive a sensingsignal. For example, the second and third sets of coupling electrodesmay be the electrodes 410 and 411 of FIG. 4A, and they may all becoupled to ones of input device electrodes 402 of FIG. 4B. In someembodiments, the same sensing signal is provided to all of deviceelectrodes 402 of FIG. 4B, and thus the second and third sets ofcoupling electrodes are coupled to the same signal.

From block 930, method 900 proceeds to block 940, where, at each of twodifferent time points, the first set of electrodes of the input deviceis provided with a reference signal, and a resulting signal is thenreceived on the second and third sets of electrodes of the input device.As noted above, the resulting signal is the same signal used to driveeach of the second and third sets of electrodes, except that when it ismeasured, it has been modified by the relative rotational positions ofthe fixed base and rotary wheel of the rotatable knob interface. Asnoted, the second and third sets of electrodes of the input device maybe driven with the same sensing signal.

From block 940, method 900 proceeds to block 950, where, based at leastin part on the data obtained at each of the two different time points, achange in rotational position and a direction of rotation of the knobinterface is determined. In one or more embodiments, this determinationmay be performed by firmware stored in a memory of the input device.

It will be appreciated that, as discussed above, blocks 920-950 of FIG.9 may be performed together with touch sensing for a respective slice inwhich the knob sensing electrodes of the rotatable knob interface islocated such that both touch and knob sensing for the respective slicein a single time instance, or blocks 920-950 of FIG. 9 may be performedin a dedicated time instance for knob sensing in which touch sensing isnot performed.

All references, including publications, patent applications, andpatents, cited herein are hereby incorporated by reference to the sameextent as if each reference were individually and specifically indicatedto be incorporated by reference and were set forth in its entiretyherein.

The use of the terms “a” and “an” and “the” and “at least one” andsimilar referents in the context of describing the invention (especiallyin the context of the following claims) are to be construed to coverboth the singular and the plural, unless otherwise indicated herein orclearly contradicted by context. The use of the term “at least one”followed by a list of one or more items (for example, “at least one of Aand B”) is to be construed to mean one item selected from the listeditems (A or B) or any combination of two or more of the listed items (Aand B), unless otherwise indicated herein or clearly contradicted bycontext. The terms “comprising,” “having,” “including,” and “containing”are to be construed as open-ended terms (i.e., meaning “including, butnot limited to,”) unless otherwise noted. Recitation of ranges of valuesherein are merely intended to serve as a shorthand method of referringindividually to each separate value falling within the range, unlessotherwise indicated herein, and each separate value is incorporated intothe specification as if it were individually recited herein. All methodsdescribed herein can be performed in any suitable order unless otherwiseindicated herein or otherwise clearly contradicted by context. The useof any and all examples, or exemplary language (e.g., “such as”)provided herein, is intended merely to better illuminate the inventionand does not pose a limitation on the scope of the invention unlessotherwise claimed. No language in the specification should be construedas indicating any non-claimed element as essential to the practice ofthe invention.

Exemplary embodiments are described herein. Variations of thoseexemplary embodiments may become apparent to those of ordinary skill inthe art upon reading the foregoing description. The inventors expectskilled artisans to employ such variations as appropriate, and theinventors intend for the invention to be practiced otherwise than asspecifically described herein. Accordingly, this invention includes allmodifications and equivalents of the subject matter recited in theclaims appended hereto as permitted by applicable law. Moreover, anycombination of the above-described elements in all possible variationsthereof is encompassed by the invention unless otherwise indicatedherein or otherwise clearly contradicted by context.

1. A rotatable knob system, comprising: a panel comprising a pluralityof sensor electrodes; and a rotatable knob interface comprising a rotarywheel and a fixed base, wherein the fixed base comprises knob sensingelectrodes and a ground pad, wherein the ground pad of the fixed base islarger than the knob sensing electrodes of the fixed base; wherein theknob sensing electrodes of the fixed base are disposed over knob sensingelectrodes of the plurality of sensor electrodes of the panel, and theground pad is disposed over reference electrodes of the panel, wherein areference area of the panel corresponding to the reference electrodes ofthe panel is larger than a knob sensing area of the panel correspondingto the knob sensing electrodes of the panel; and wherein the panelcomprises a plurality of traces which connect the knob sensingelectrodes of the panel to a processing system, and wherein theplurality of traces connecting the knob sensing electrodes of the panelto the processing system do not overlap with the reference electrodes ofthe panel.
 2. The rotatable knob system according to claim 1, whereinthe panel is a touch-sensitive display panel.
 3. The rotatable knobsystem according to claim 1, wherein the panel comprises a plurality ofslices corresponding respectively to a plurality of analog front ends(AFEs), wherein the plurality of sensor electrodes of the panel includea first plurality of sensor electrodes corresponding to a first slice ofthe plurality of slices and a second plurality of sensor electrodescorresponding to a second slice of the plurality of slices.
 4. Therotatable knob system according to claim 3, wherein the ground pad ofthe fixed base is disposed over the first slice, and wherein the knobsensing electrodes of the fixed base are disposed over the second slice.5. The rotatable knob system according to claim 3, wherein the groundpad of the fixed base and the knob sensing electrodes of the fixed baseare disposed in the same slice.
 6. The rotatable knob system accordingto claim 3, wherein the knob sensing electrodes of the fixed base aredisposed over the second slice; wherein the system further comprises theprocessing system; and wherein the processing system is configured toperform knob sensing via the knob sensing electrodes of the panel in asame time instance as performing touch sensing for the second slice. 7.The rotatable knob system according to claim 3, wherein the knob sensingelectrodes of the fixed base are disposed over the second slice; whereinthe system further comprises the processing system; and wherein theprocessing system is configured to perform knob sensing via the knobsensing electrodes of the panel in a time instance during which touchsensing is not performed.
 8. A rotatable knob system, comprising: apanel comprising a plurality of sensor electrodes; and a rotatable knobinterface comprising a rotary wheel and a fixed base, wherein the fixedbase comprises knob sensing electrodes and a ground pad, wherein theground pad of the fixed base is larger than the knob sensing electrodesof the fixed base; wherein the knob sensing electrodes of the fixed baseare disposed over knob sensing electrodes of the plurality of sensorelectrodes of the panel, and the ground pad is disposed over referenceelectrodes of the panel, wherein a reference area of the panelcorresponding to the reference electrodes of the panel is larger than aknob sensing area of the panel corresponding to the knob sensingelectrodes of the panel; and wherein the panel comprises a firstplurality of traces which connect the knob sensing electrodes of thepanel to a processing system and a second plurality of traces whichconnect the reference electrodes of the panel to the processing system,wherein the second plurality of traces are separate from the firstplurality of traces.
 9. The rotatable knob system according to claim 8,wherein the panel is a touch-sensitive display panel.
 10. The rotatableknob system according to claim 8, wherein the panel comprises aplurality of slices corresponding respectively to a plurality of analogfront ends (AFEs), wherein the plurality of sensor electrodes of thepanel include a first plurality of sensor electrodes corresponding to afirst slice of the plurality of slices and a second plurality of sensorelectrodes corresponding to a second slice of the plurality of slices.11. The rotatable knob system according to claim 10, wherein the groundpad of the fixed base is disposed over the first slice, and wherein theknob sensing electrodes of the fixed base are disposed over the secondslice.
 12. The rotatable knob system according to claim 10, wherein theground pad of the fixed base and the knob sensing electrodes of thefixed base are disposed in the same slice.
 13. The rotatable knob systemaccording to claim 10, wherein the knob sensing electrodes of the fixedbase are disposed over the second slice; wherein the system furthercomprises the processing system; and wherein the processing system isconfigured to perform knob sensing via the knob sensing electrodes ofthe panel in a same time instance as performing touch sensing for thesecond slice.
 14. The rotatable knob system according to claim 10,wherein the knob sensing electrodes of the fixed base are disposed overthe second slice; wherein the system further comprises the processingsystem; and wherein the processing system is configured to perform knobsensing via the knob sensing electrodes of the panel in a time instanceduring which touch sensing is not performed.
 15. A method for knobsensing, comprising: providing a rotatable knob interface on a panel ofan input device, the knob interface having a fixed base and a rotarywheel, wherein the panel comprises a plurality of sensor electrodes,wherein the fixed base comprises knob sensing electrodes and a groundpad, wherein the ground pad of the fixed base is larger than the knobsensing electrodes of the fixed base, wherein the knob sensingelectrodes of the fixed base are disposed over knob sensing electrodesof the plurality of sensor electrodes of the panel, and the ground padis disposed over reference electrodes of the panel, wherein a referencearea of the panel corresponding to the reference electrodes of the panelis larger than a knob sensing area of the panel corresponding to theknob sensing electrodes of the panel, wherein the panel comprises aplurality of traces which connect the knob sensing electrodes of thepanel to a processing system of the input device, and wherein theplurality of traces connecting the knob sensing electrodes of the panelto the processing system do not overlap with the reference electrodes ofthe panel; providing, by the processing system, a reference signal tothe reference electrodes of the panel and sensing signals to the knobsensing electrodes of the panel; obtaining, by the processing system,resulting signals via the knob sensing electrodes of the panel; anddetermining a change in rotational position and a direction of rotationof the knob interface based, at least in part, on the obtained resultingsignals.
 16. The method according to claim 15, wherein the panelcomprises a plurality of slices corresponding respectively to aplurality of analog front ends (AFEs), wherein the plurality of sensorelectrodes of the panel include a first plurality of sensor electrodescorresponding to a first slice of the plurality of slices and a secondplurality of sensor electrodes corresponding to a second slice of theplurality of slices.
 17. The method according to claim 16, wherein theground pad of the fixed base is disposed over the first slice, andwherein the knob sensing electrodes of the fixed base are disposed overthe second slice.
 18. The method according to claim 16, wherein theground pad of the fixed base and the knob sensing electrodes of thefixed base are disposed in the same slice.
 19. The rotatable knob systemaccording to claim 16, wherein the knob sensing electrodes of the fixedbase are disposed over the second slice; and wherein knob sensing isperformed via the knob sensing electrodes of the panel in a same timeinstance as performing touch sensing for the second slice.
 20. Therotatable knob system according to claim 16, wherein the knob sensingelectrodes of the fixed base are disposed over the second slice; andwherein knob sensing is performed via the knob sensing electrodes of thepanel in a time instance during which touch sensing is not performed.